The Lick Creek Demonstration — Forest
Renewal Through Partial Harvest and Fire
Benjamin Zamora1 and Melinda Martin2
Abstract—The Lick Creek Demonstration Site on the Pomeroy Ranger District, Umatilla
National Forest, is a Joint Fire Science Program sponsored project to create a demonstration of the effects of fuels management on forest health. The project was initiated
in 2001 and involved the integration of two levels of partial harvest with prescribed
fire, a burn only treatment and an untreated control treatment. Biomass utilization was
incorporated into the burn preparation following harvest. Objectives of the treatments
were to improve stand composition and structure, reduce fuel levels, and enhance
wildlife habitat. Units were harvested in 2001. Prescribed fire as applied in 2004.
Monitoring of fuels and stand attributes was implemented in 2005. Harvest reduced
overstory canopy coverage as much as 70%. Understory tree layers remained intact
through the harvest but were significantly affected by the prescribed burn. Herbage
production increased in areas of moderate fire intensity but showed little response in
areas of high fire intensity. Less than 1% mortality was evident in 2005 among leave
trees in the treatment units but tree conditions indicate future higher mortality. Fuels
reduction was the most uniform in the commercial yarding treatments but was highly
varied in the burn only treatments. Contractor revenue profits from the harvest and
biomass fuel were modest and dependent on the provision of service contracts by
the USFS Pomeroy Ranger District in addition to the release of the products to the
contractors for independent sale.
Introduction
In 2000, the Joint Fire Science Program (JFSP) requested grant proposals
for development of fuels management demonstration sites throughout the
United States. The sites were to provide the public and research interests
opportunity to observe the effects of fuels management involving prescribed
fi re on wildland ecosystems. The Pomeroy Ranger District of the Umatilla
National Forest in southeastern Washington, in conjunction with Washington
State University, received a grant from the JSFP to initiate the development
of the Lick Creek Demonstration Site in the northern Blue Mountains of
southeastern Washington. The project period was originally set for a three-year
period from FY 2001 through FY 2003. The last of the project components
was completed in 2005.
The overall goal of the Lick Creek project was to develop a demonstration
of the application and effects of selective, partial harvest on mid-succession
forest stands in combination with prescribed fi re to enhance forest condition,
amenities, and reduce wildfi re hazard. Frequent and timely monitoring of the
demonstration site would provide documentation to substantiate, clarify, and
USDA Forest Service Proceedings RMRS-P-41. 2006.
In: Andrews, Patricia L.; Butler, Bret W.,
comps. 2006. Fuels Management—How to
Measure Success: Conference Proceedings.
28-30 March 2006; Portland, OR.
Proceedings RMRS-P-41. Fort Collins,
CO: U.S. Department of Agriculture,
Forest Service, Rocky Mountain Research
Station.
1 Associate Professor and Scientist,
Natural Resource Sciences, Washington
S t at e Un i ve r s it y, P u l l m a n , WA .
bzamora@wsu.edu.
2
Fire Planner, Fire/Fuels Management, Pomeroy Ranger District, USFS
Umatilla National Forest, Pomeroy, WA.
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The Lick Creek Demonstration — Forest Renewal Through Partial Harvest and Fire
explain anticipated ecological relationships and treatment effects throughout
the demonstration site. The demonstration was to provide opportunity for
general public examination and for the Pomeroy Ranger District to begin a
long-term monitoring study of a fuels management strategy applied throughout the District.
Efforts to achieve public understanding and support of forest practices to
rectify forest health issues is a priority in the Pomeroy Ranger District because
of the sensitivity of the forest landscapes and the multiple interests in the
public lands of the District. Successful implementation of any forest practice
in the District is predicated on public support. The Lick Creek Demonstration is intended to show how forest practices can enhance forest landscapes
for tree growth, wildlife habitat, and reduction of wildfi re hazard.
The purpose of this proceedings paper is to provide a synopsis of the character and development of the demonstration site.
Objectives
The specific objectives of the project were (1) to implement four levels of
viewable silvicultural and fuels management stand treatment on the Lick Creek
site in a replicated manner, (2) prepare documentation of the treatments and
treatment effects for public review, (3) initiate a long-term monitoring study
of the site to document treatment effects to include response of leave trees,
and (4) to assess the economic viability of small diameter timber harvest as a
means of accomplishing silvicultural and fuels management objectives. The
treatments would represent prescription strategies currently employed by
District staff to address management of stand structure, species composition,
and fuel conditions in mid-successional forest stands.
Site Location and Pretreatment Vegetation
Character
The Lick Creek Demonstration Site lies within the Blue Mountains Physiographic Province of southeastern Washington (Fig. 1). The site is located in
the eastern portion of the Pomeroy Ranger District of the Umatilla National
Forest and centered at longitude 117.4833°, latitude 46.2333°. The general
terrain of the area is a deeply dissected plateau to the south and east of the
Snake River Canyon that traverses through southeastern Washington. The
specific site terrain is a steep, dissected canyon slope between 4100-5100 ft
elevation with aspects spanning northwest to northeast. Slopes average 50 to
60% across the entire site. The area is within the rain shadow cast by the
central Blue Mountains ridge, thus is within a dry subhumid climate. Total
annual precipitation is ±35 inches with effective moisture varying according
to topographic and soil conditions.
The vegetation of the site is a mosaic of forest stands interspersed with
grassland sites on side-ridges and shallow soils (Fig. 2). Generally, two distinct zones of vegetation are distinguishable across the site. An upper canyon
wall zone of the Douglas-fi r/snowberry (Pseudotsuga menziesii/Symphoricarpos albus) and Douglas-fi r/ninebark (Pseudotsuga menziesii/Physocarpus
malvaceus) plant associations covers from 1 ⁄4 to 1 ⁄ 3 of the site slope surface
(Johnson and Clausnitzer 1992). The width of this zone is dependent on
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Zamora and Martin
Figure 1—Location of the Lick Creek Demonstration Site in the Pomeroy Ranger District,
Umatilla National Forest, southeastern Washington.
Figure 2—Pre-harvest photograph of the Lick Creek Demonstration Site looking east
along the face of the site in 2000.
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The Lick Creek Demonstration — Forest Renewal Through Partial Harvest and Fire
slope surface configuration with the narrowest portions associated with concave surfaces and the broadest portions associated with convex surfaces. The
lower 2 ⁄ 3 to 3 ⁄4 of the canyon wall is dominated by the grand fi r/twinflower
(Abies grandis/ Linnaea borealis) plant association. Ponderosa pine (Pinus
ponderosa) and western larch (Larix occidentalis) are the seral conifer tree
species throughout the site.
The existing vegetation over the site prior to treatment generally reflected a
mid-successional state (Fig. 3). Most of the area supported a sparse component
of 100+ year-old trees of ponderosa pine, western larch, and Douglas-fi r that
formed an upper overstory layer with canopy cover ranging from 5-15%. Tree
heights were 90 ft with average d.b.h. ranging from 20 to 32 inches. The
majority of the leave trees in the harvest treatments were in this particular
cohort. The bulk of the forest canopy was a deep mid-story tree layer composed predominantly of Douglas-fi r (67%) and grand fi r (24%) with sparse
ponderosa pine (6%) and western larch (3%). Average height of trees within
this layer ranged from 45 to 50 ft and averaged 9 to 11 inches d.b.h. Most
of the merchantable timber came from this mid-story layer. A distinct third
cohart of smaller trees with 3 to 6 inches d.b.h. occurred in the lower portion
of the layer between 20 and 40 ft. These smaller trees composed 53% of the
total tree density of the layer, and in combination with an understory layer
of junvenile trees less than 3 inches d.b.h. and under 10 ft in height, formed
the greatest barrier to light penetration to the ground surface.
Figure 3—Example of pre-harvest stand conditions in the Lick Creek Demonstration Site.
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History of the Site
The Problem
The Lick Creek site was selectively harvested through several entries during
the 1960’s and early 1970’s for large diameter sawlogs by means of a skyline
system. No additional harvest or fuels treatment have occurred on the site
since that time. There is no evidence of wildfi re in the immediate drainage
area of the site in the past 100+ years so the site represents a fi re exclusion
location. Stand development since the 1960’s progressed to mid-successional
stages of overstocked, nearly closed stands of small diameter, shade-tolerant
Douglas-fi r and grand fi r. Competition from these shade-tolerant species reduced the abundance of shade-intolerant ponderosa pine and western larch. In
addition, surface and ladder fuels were accumulating to the point of creating
a severe surface and crown wildfi re hazard (Fujishin 1998).
The drainage lies directly above a major Rocky Mountain elk winter range in the
Asotin Creek watershed adjacent to the Snake River and is a significant part of
a spring elk calving area and summer range for elk herds that utilize the Asotin
Creek winter range. Stand closure of forests within the Lick Creek drainage
was reducing the diversity and abundance of the understory and detrimentally
affecting the quality of elk and wildlife habitat (Lorentz 1997).
The Solution
The prescription for stand management on the Lick Creek site revolved
around the principal objectives of opening stands, shifting the balance of
species composition to favor ponderosa pine and western larch, and reducing fuel loading (Bott 1998). Selective harvest and thinning from below
combined with prescribed fi re was prescribed to accomplish the objectives
The efficacy of these practices was considered to be well established (Agee
1996, Applegate and others 1997, Graham and others 1999, Williams and
others 1993). Multiple entries over time with prescribed fi re after harvest
was thought necessary in order to ultimately achieve the objectives of the
prescription (Martin 1998). The treatment effects of the combined practices
were also expected to enhance wildlife habitat in general, and more specifically,
the elk habitat of the site that is a central concern to several local public interest groups. Untreated wildlife leave units were integrated into the treatment
design to serve a wildlife cover and travel corridors. Non-hazardous snags
where left standing and a buffer zone was designated along the bottom of
the Lick Creek drainage to protect watershed values and provide additional
undisturbed wildlife cover.
Two primary concerns were identified in the development of the Lick Creek
Demonstration prescription and are reflected as inclusions in the project objectives. These were (1) the effects of fi re on leave trees and (2) the economic
viability of small diameter timber harvest.
The mortality of large leave trees from prescribed fi re across the Lick
Creek site was a major concern (Martin 1998). Several recent studies have
confi rmed that mortality of trees from a prescribed fi re increases as the depth
of the duff layer around the base of the tree and the diameter of tree bole
increases (Ryan and Frandsen 1995, Hille and Stephens 2005, Stephens
and Finney 2002, Thies and others 2006). Documentation of the leave tree
post-burn responses was designated as a priority element in the monitoring
of the demonstration site.
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The majority of the merchantable sawlog trees on the Lick Creek site
grade as small diameter timber (5-9 inches d.b.h.), raising questions about
the profitability of such a harvest to logging contractors and their interest in
undertaking this kind of harvest option. Selective harvest and thinning of
small diameter stands is being increasingly considered in the Interior Northwest as a means of reducing wildfi re hazard, redistributing tree growth, and
re-directing stand development (Wagner and others 1997, Baumgartner and
others 2002). But questions remain about the fi nancial viability of such harvest from the standpoint of product marketability and revenue and harvest
costs (Johnson 1997, Wagner and others 1997). Harvest costs are affected
by tree size and utilization with harvest costs inversely proportional to tree
size—small-diameter trees result in small piece sizes with low volumes and are
more costly to handle (Stokes and Klepac 1997). Johnson (1997) stated that
an economical harvest of small trees is difficult to attain for two reasons—the
cost per unit of volume to move the material increases dramatically as diameter of the volume decreases, and the value of the unit volume decreases
as piece size decreases. Harvest costs increase with reduced road accessibility and conditions, less steeper and more complex terrain, smaller trees and
higher density stands, limited opportunity to use less expensive mechanical
yarding, and greater hauling distance. Ultimately, the availability of stable
markets for multiple wood products from the harvest will dictate net profit
from the harvest (Johnson 1997, Stokes and Klepec 1997). Documentation
and evaluation of harvest and fuels treatment costs and product revenues to
assess economic viability of the silvicultural and fuels management strategy
was included as a primary objective of the project.
Methods
Treatment Design and Installation
The site was divided into three treatment units with wildlife habitat units left
between some of the treatment units within the site boundaries (Fig. 4). A 150
ft buffer zone was maintained of at the bottom of the slope between the treatment units and Lick Creek. Each unit was divided into four subunits to replicate
the treatment. The following four treatments were installed in each unit—two
levels of harvest, a control, and a burn only treatment (Table 1). The replication
subunits range in size from 6 to 17 acres, the size being dictated by uniformity
of pre-harvest conditions and the facilitation of harvest and prescribed burning
operations.
Treatment Schedule
Treatment planning, the timber cruise, and pre-logging stand inventory
were conducted in 2000 and 2001. Harvest of the site was completed during
the winter of 2001-2002. Preburn inventory was conducted in 2002-2003.
Slash piles were removed from the site by means of chipping and selected
pile burns in the fall of 2003. The prescribed burn of the treatment units
was conducted in September and October 2004. The fi rst year of post-burn
monitoring was completed in the summer and fall of 2005.
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Figure 4—Aerial view of treatments at mid-elevation within the Lick Creek Demonstration
Site showing fuels yarding (a, c) on a wildlife leave unit (b) above Lick Creek (d).
Permanent monitoring plots are distributed near the center of each unit from top to
bottom.
Table 1—Replicate (3) treatments implemented on the Lick Creek Demonstration Site, Blue Mountains,
Pomeroy Ranger District, Umatilla National Forest.
Treatment
Description
Control
No harvest, no prescribed burn - stand left in original state.
Prescribed burn only
No harvest, prescribed burn of stand in its original state.
Commercial yarding - prescribed burn
All trees unmarked as leave trees that were 6 inches d.b.h.
or greater that had a minimum 8 foot long piece to a 3 inch
top were cut and removed to the landings, whole tree yarding
was not required but generally done to improve efficiency of
operation; post-harvest prescribed burn was applied. Objective
of treatment was to leave a greater quanity of fuel in place on
the units.
Fuels yarding - prescribed burn
All trees unmarked as leave trees that were 3 inches d.b.h. or
greater that had a minimum 8 foot long piece to a 3 inch top
were cut and removed to the landings; whole tree yarding was
required; down material meeting the cutting specifications for
commercial yarding (6+ inches d.b.h.) were cut and yarded;
post-harvest prescribed burn was applied. Objective of
treatment was to minimize fuel accumulations on the units.
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Harvest
A total of 85 acres of the site were harvested in a 40-day period, commencing in mid December 2001. Winter logging in the Blue Mountains is at risk
of being stopped at any time because of severe storm conditions and snow
accumulation. Fortunately, severe weather conditions never developed until
after the harvest had been completed in late January, 2002, allowing harvest
to proceed with minimal snow cover.
Yarding was conducted for 74% of the harvest area with gravity feed skyline
system utilizing a skyline yarder and a motorized support carriage. Groundbased yarding with a tracked skidder was conducted over the remaining 26%
of the harvest area. Whole tree yarding was required as part of the treatment
prescription to minimize fuel loading on the site.
A stationary, pull-through, motorized, radio-controlled delimber was used
to process the whole trees that were yarded to the landing. After delimbing,
the trees were sorted according to merchantable (sawlog) or unmerchantable (tonwood, fiber wood), cut to specified lengths, and piled into decks for
loading. One-hundred loads were hauled from the site—51 sawlog loads,
33 tonwood loads, and 16 fiber loads.
The total yield of the harvest averaged 27.14 tons per acre for the 85-acre
harvest area of the Lick Creek Site. Yield was portioned as follows - sawlog
(1171 t, ~ 194 gross mbf), tonwood (761 t), fiber wood (374 t).
Chipping for Biomass Fuel
Whole tree removal from the harvest site meant that large slash piles accumulated at the landings at the top of each unit. These piles were large,
ranging from 1.41 tons/acre to 4.67 tons/acre and were considered a hazard
to the conduct of the prescribed burn because of their location and potential
to initiate escape fi re. Removal of the piles proceeded in the late fall of 2003
through a service contract to a local contractor to chip the slash for sale as
biomass fuel. Because of limited road access, the chipper was stationed at a
site that provided access to haul trucks. Slash from the piles was transported
by trucks to the chipper for processing. Slippage of some slash piles down the
steep slopes of the site made some of the slash inaccessible to loaders. This
material was pile burned after the slash chipping had been completed. A total
of 33 piles yielded 482.44 dry t of chipped wood for sale as biomass fuel.
Prescribed Burn
The burn was conducted from in a 5-day period from September 30October 4, 2004. The burn prescription targeted reduction of fuels and
understory fi re-intolerant and shade-tolerant tree species on the site as the
principal objectives. The principal Ignition pattern was strip head-fi re over
most of the site with backing fi re used through heavy fuel accumulations and
down very steep slopes. Flame-lengths were to be kept under 4 ft to limit
fi re intensity. Seven burn units are designated, combining treatment units
to facilitate control and consistency in the character of the burn. Ignitions
started at highest points of the site and progressed down-slope and to lower
elevations within the site over the burn period. Surface fuels were typically
a mosaic of grass and woody fuel patches, intermixed with live shrub and
tree materials. The small live tree component was especially significant in
the higher elevation units. The live shrub component was most significant in
the lower elevation and environmentally warmer units. Woody fuel loading
varies across the Lick Creek site according to treatment. The highest woody
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fuel loadings were in the commercial yarding units harvest with fuelbeds
in the Fire Behaviror Fuel Model 10 and 11 categories depending on the
mix of herbaceous and live fuels and amount of overstory.
At the beginning of the burn period, temperatures (55-62 ° F) and relative
humidity (38-44%) were near the lower limit of the burn prescription providing an advantage in keeping fi re intensity low while still accomplishing the
prescription objectives. Backing fi res were ineffective under these conditions,
so strip head-fi re ignition was the principal means of ignition. Temperatures
climbed into the low 70’s and humidity dropped into the high 20’s by the
end of the 5-day burn period and back-fi ring became the principal means of
fi re spread. Winds occurred in the typical fall convective wind pattern and
were not a factor at anytime during the burn period.
Initial estimates indicate that an average reduction of 80% was achieved in
the woody fuel and ground fuel loading over the Lick Creek site.
Monitoring System
Five permanent plots are distributed within each treatment unit near
the center from the top to the bottom of the unit (Fig. 4). The plots were
inventoried pre- and post-burn. Pre-harvest plots were sampled in the same
locality as the permanent plots but do not represent the exact location of the
permanent plots. The plot is circular with a diameter of 50 m. The center of
the plot is the photo point from which a radial sequence of photos is taken
of the entire perimeter of the plot. Two 25-m transects from the plot center
along the contour of the slope are used to collect point and microplot data
for the following overstory and understory attributes: fuel loading, species
composition and canopy coverage, tree density by diameter class and species, stand canopy stratification, height, and composition, and soil surface
coverage and composition. A series of digital photos are taken of 1-m 2 microplots along each transect. The data is being entered and summarized in
FIREMON (2006).
Summary of Preliminary Findings
Stand structure was significantly altered by harvest with reductions of
overstory canopy coverage by as much as 70% in some treatments. The
majority of the dominant mid-story canopy layer was eliminated by the
harvest. However, a substantial amount of the understory tree layer of short
and less than 3 inches d.b.h. remained intact after harvest. The prescribed
burn damaged the majority of the understory layer but the full extent of the
mortality was not fully expressed in the 2005 inventory. Herbage production
increased dramatically in areas of moderate fi re intensity but did not show
a similar response in areas of high fi re intensity. Less than 1% mortality was
evident in 2005 in the leave tree populations across all of the harvest treatment units. A low degree of mortality is evident in the overstory of the burn
only treatments but the condition of many of the trees suggest that greater
levels of mortality are to be expected in coming years. Fuels reduction varied
greatly among treatment replications with the most uniformity reduction in
the commercial yarding treatments and the greatest variation in the burn
only treatments. Contractor revenue profits from the harvest and biomass
fuel were modest and dependent on the provision of service contracts by the
USFS Pomeroy Ranger District in addition to the release of the products to
the contractors for independent sale.
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Project Sponsors
Funding to initiate the development of the Lick Creek Demonstration Site
was provided by the Joint Fire Science Program, USFS Umatilla National
Forest, Washington State University, Rocky Mountain Elk Foundation, Blue
Mountain Elk Initiative, and Guy Bennett Lumber Company.
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